Fuel cells can be classified into polymer electrolyte membrane fuel cells (PEMFCs), direct methanol fuel cells (DMFCs), alkaline fuel cells (AFCs), phosphoric acid fuel cells (PAFCs), molten carbonate fuel cells (MCFCs), solid oxide fuel cells (SOFCs), and the like depending on the types of electrolyte used and fuel used. Further, the working temperature of fuel cells and constituent part materials thereof vary depending on the type of electrolyte used.
Among them, a solid oxide fuel cell is a type of fuel cell which is an energy conversion device to directly convert chemical energy having hydrogen and oxygen into electric energy by electrochemical reactions, and has received attention as a next-generation energy conversion device due to many advantages in terms of high conversion efficiency and eco-friendliness.
In this case, it is preferred that an electrolyte membrane in the solid oxide fuel cell is thin and dense. Thus, studies for developing particles suitable as an electrolyte material for a solid oxide fuel cell have been conducted.